The subject application relates generally to corn headers for use with agricultural harvesters. In particular, the subject application relates to a power takeoff drive assembly for a corn header of an agricultural harvester.
Agricultural harvesters such as combines that harvest corn are provided with headers including row dividers for directing rows of corn stalks to ear separation chambers or row units comprising stripping plates (or deck plates) defining a stalk receiving slot or gap therebetween. The row units further include snapping rolls (or stalk rolls) located beneath the deck plates and endless gathering chains located above the deck plates. As the combine traverses a field, the row dividers divide the stalks into rows of individual stalks which are pulled downwardly by the rotating stalk rolls. The downward pulling of the stalks by the stalk rolls causes the ears of corn to forcefully strike the deck plates whereupon they are snapped off the stalks. The gathering chains run fore to aft along the row units and transport the stripped corn to a conveyor for conveying the harvested corn to a feederhouse of the combine. Harvested corn is then processed to the combine's inner chambers for downstream processing. Stalks stripped of corn by the row units are commonly processed by chopping units having cutting blades located beneath the stalk rolls that chop the stalks, leaves, etc. (also known as “material other than grain” or “MOG”) into finer pieces which are then distributed onto the field being harvested.
Many conventional systems drive both the row units and chopping units by a single rotating cross shaft or line shaft that derives its power from a power takeoff (PTO) connected to the drive train of the combine. That is, the moving parts of the row units, e.g., the stalk rolls and gathering chains, as well as the cutting blades of the chopping units are driven by a single line shaft. The number of row units and chopping units a single line shaft can drive is limited by the size, e.g., diameter, of the line shaft and the line shaft rotational speed. On larger headers, e.g., those having twelve or more row units, the power from the combine and PTO is run laterally outwardly across the rear of the header to the lateral ends of the header, then forwardly to the front of the header and then back to the center of the header via the line shaft. On conventional larger headers, therefore, this arrangement requires two drives, one on each end of the header for delivering power from the rear of the header to the front thereof. However, the provision of gearboxes on opposite ends of the header increases the width of the header. In so doing, the width of the header is greater than would otherwise be desirable as is the number of parts necessary to rotate the line shaft(s).